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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Návrh podvozku malého dvoumístného letounu / Landing gear design of two-seat airplane

Čavojský, Tomáš January 2021 (has links)
This diploma thesis deals with the landing gear design of the small two-seat aircraft. The introduction focuses on the conceptual gear design and shock absorber computational dynamic characteristic model. The practical part is focused on the landing gear construction according to the selected parameters based on the conceptual and computational model. The diploma thesis ends with strength calculations and production documentation.
2

Strategy for Product Development in the Gear Production Industry ¡V Company A as Research Subject

Liao, Kun-lung 19 August 2011 (has links)
The study is based on the thirty years operation experience from the author. The author enhance the enterprise management and improve the product innovation ability by investigating the enterprise management strategy and resource employ theory. Through the motivation, process and turn-key solution development by the innovated product, the author generalize the knowledge of strategy management and response the challenge of global industry competition. In Chapter 3, the author describe the development history and status analysis of the gear industry. The author also indicate the focal point and core advantage of the innovated product. With ECO-Friendly¡BEnergy Saving properties design, the product had been affirmed by the customers and acquired the 2010 Taiwan Innovation Research and Development First Prize Award¡B2010 Taiwan Nation Gold Medal¡B2011 Taiwan Excellence Award¡B2011 Switzerland Geneva Invention Gold Medal and 2011 Italy Catania Invention Gold Medal. The author study the global market opportunity and further plan the new development strategy for market expansion. In Chapter 4, the author divided the research method into the case analysis method and the grounded theory method. The author use apply the practical data collection method and strict qualitative analysis method to verify the accuracy of the collected data, then draw out the effective management strategy. In Chapter 5, the author compare the difference between the innovated product V.S. the traditional product and figure out its competitive advantage. Through the actual testing data illustration, the author explain the contribution of the innovated product and the relationship between the enterprise responsibility afford and the enterprise sustainable operation. The author expect to strength the company's innovated strategy management ability via the innovated product development. At the same time, the author wish to inspire the the passion of machinery industry innovated design and encourage the new designer to be more creative and implement their good design idea.
3

A Study on the Bevel Gear with Circular-Arc Tooth Profiles

Kuo, Hsiu-Ming 23 July 2001 (has links)
Nowadays, the bevel gears are widely applied in the industry for the intersected-axial transmission system. But the applications of the bevel gears are mostly limited to the usage of involute bevel gears. In this thesis, the bevel gear with circular-arc tooth profiles is derived by using general theorem of conjugate surfaces, coordinate transformation, constrained meshing equation, and spherical trigonometry. According to the bevel gears with circular-arc tooth profile derived above, the analyses and discussions of the interference are proposed. The interference situation is detected by applying the phase lead-lag concept while circular-arc curve is moving on the spherical cross-section. Furthermore, the ideal conditions to avoid occurrence of interference are proposed. Design charts for the maximum values of tooth profile angle are also constructed as a reference for designers. The 3D solid models of the bevel gear with circular-arc tooth profiles are constructed by using the computer software (Pro/E). Finally, the transmission ability is verified through the computer animation using CAE software (Visual Nastran). It is believed that the mathematical models and design method developed in the thesis will provide a useful foundation for the further studies.
4

Reduction of by-catch in the brown shrimp, Crangon crangon, fisheries of the Wash and Humber estuaries

Graham, Giles Norman January 1997 (has links)
No description available.
5

Scuffing at high speed and temperature

Nicolson, David Macnab January 1996 (has links)
No description available.
6

The use of high frequency stress waves for monitoring gears

Al-Balushi, Khamis Rajab Nasser January 1995 (has links)
The aim of this research is to investigate the feasibility of using stress waves for condition monitoring of gears. The project involved setting up an experimental rig, carrying out experimental work, acquiring stress waves signatures, and processing the signals. It has been shown that stress waves can successfully be employed for early detection of incipient gear failure. A experimental gearbox was employed during the experiments. Miniature ultrasound transducers, both sensitive and sufficiently small, were manufactured and installed on the stationary outer race of the rolling element bearing of the gearbox to detect stress waves from the meshing gears. The stress waves signals from the transducers were digitised and digitally processed to extract relevant information. The signatures were high-pass filtered at a cut-off frequency of 200 kHz, thus representing exclusive ultrasonic frequencies. A new statistical parameter, Energy Index, was developed and performed on the stress wave signatures which were segmented to represent individual gear teeth. Along with this new parameter, the classical statistical parameters, (Peaks, RMS, Standard Deviation, Kurtosis, etc.) were also performed. Conclusive results are presented in graphical form in terms of Cumulative Energy Indices' and Energy Indices in polar form for individual gear teeth. A new algorithrn was also developed and presented for the envelope detection of signal by iterative peak detection. Although no direct comparison was made between condition monitoring of gears using stress waves and methods such as low frequency vibration analysis and wear debris analysis, it is apparent that stress waves monitoring offers a much earlier warning of incipient gear failure because the technique can detect material defonnations which are precursors to changes in the dynamic properties of gears and the occurrence of wear debris. The technique, therefore, can predict incipient failure much earlier, extending the lead-time before failure, and as a result, minimising sudden failures which may have catastrophic consequences.
7

Design of Five-speed Automatic Transmissions for Automobiles

Yang, Zhi-Ren 07 July 2000 (has links)
Planetary gear trains have the advantages of compactness, light weight, high speed reduction and differential drive, and can provide several speed ratios by means of selecting different clutches and brakes. They are widely used in the automatic transmissions for automobiles. The purpose of this work is to develop a systematic methodology for the design of automatic transmissions for automobiles. First, the specification is established by using concept of fundamental geared entities. Second, a methodology of structure synthesis is developed for establishing gear trains graphs table with up to three fundamental geared entities. Third, a method for systematically enumerating all possible clutching sequences is established and a method for position of clutches and brakes is developed to establish automatic transmissions graphs table. Forth, a procedure for the selecting of a most efficient clutching sequence associated with a automatic transmission is developed. Finally, the systematic theory integrates preceding methodologies and a computer software package is to developed. The computer software package provides user a powerful tool to design automatic transmissions for automobiles.
8

The effects of torsional-lateral coupling on the dynamics of a gear coupled rotor

Emery, Michael Aaron 25 April 2007 (has links)
This thesis focuses on the torsional-lateral interactions seen in gear coupled rotors. Of particular interest are cases where the torsional stiffness parameters affect the lateral critical speeds and where lateral stiffness and damping parameters affect torsional critical speeds and amplitudes. A common procedure for critical speed calculations has been to solve lateral and torsional systems separately. This procedure is tested through an eigenvalue analysis. It is shown in this thesis, however, that torsional-lateral interactions play major roles in each other's critical speeds. Some research has seemingly uncoupled two lateral degrees of freedom from the gear system by choosing bearing forces and a coordinate system pointing along the line of action and normal to the line of action. This simplification method has been tested for cases when the lateral bearing stiffness becomes asymmetric. The force generated by a rotating imbalance also creates a variable moment arm as the center of mass rotates about the geometric center of the gear. This variable moment arm is commonly neglected, but is included in the last case study and its effects are displayed in the results section of this thesis.
9

The theoretical flow ripple of an external gear pump /

Kasaragadda, Suresh Babu. January 2003 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 50-51). Also available on the Internet.
10

The theoretical flow ripple of an external gear pump

Kasaragadda, Suresh Babu. January 2003 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 50-51). Also available on the Internet.

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